The present invention relates generally to article handling apparatus and methods and, more particularly, to a novel method and apparatus for handling articles having opposite ends or other portions having differing stretch characteristics.
Across substantially all industries, the desire to improve efficiency and productivity while at the same time to reduce costs has provided the impetus for an ever increasing automation of various manufacturing steps. Nevertheless, the automated handling of manufactured articles having a flaccid character presents considerable difficulty. By way of example but without limitation, the textile industry has been successful in automating many of the steps in the manufacture and processing of socks and other hosiery articles, but it still largely remains necessary for human operators to perform various steps in the overall manufacturing operation, such as manually placing hosiery articles on the forms of a hosiery boarding machine.
One of the fundamental difficulties in automating the handling of flaccid articles such as hosiery is that the flaccid character of the articles makes it difficult, if not impossible, to maintain the articles in a consistently uniform orientation while being transported or otherwise handled. For example, the vast majority of conventional hosiery articles are made of circularly knitted fabric initially produced in a tubular form commonly referred to as a xe2x80x9cblankxe2x80x9d which, in most cases, has a distinct toe portion at one tubular end and a differently fashioned cuff portion at the opposite tubular end. In the handling of such articles subsequent to the initial knitting of the tubular blank, it is therefore important, if not critical, that the toe and cuff ends be differentiated. For example, in order to sew closed the toe end portion of a hosiery blank, it is essential that the toe end rather than the cuff end be presented to the sewing device. Conventionally, the feeding or placement of a hosiery article in correct orientation for such operations is performed manually, despite the significant labor cost such a manual operation adds to the overall hosiery manufacturing process.
Accordingly, a substantial need exists within not only the textile industry but substantially any industry involved in the manufacture or other handling of flaccid articles such as hosiery to automate the function of uniformly orienting such articles and, in particular, to automate the threshold step of recognizing different portions of such articles which have distinguishing physical characteristics.
It is accordingly an object of the present invention to provide a novel method and apparatus for automatically distinguishing from one another physically differing portions of the article. A more particular object of the present invention is to provide a novel method and apparatus by which differing portions of an article having differential stretch characteristics may be automatically distinguished from one another. A further object of the present invention is to provide a method and apparatus by which the opposite ends of a hosiery article may be distinguished from one another as a result of their respectively differing stretch characteristics.
Briefly summarized, the present invention addresses these objectives by providing a method and apparatus basically operable to apply a stretching force to one of first and second differentially stretchable portions of an article and to detect a reaction of the one portion in response to the stretching force to obtain an indication of which of the first and second portions was stretched.
In a preferred embodiment of the present method and apparatus, the stretching force is applied by a device operative to grasp the one portion of the article at spaced locations thereon and to move the spaced locations further apart. The reaction of the one portion of the article to the stretching force may preferably be detected by a sensor which detects the amount by which the article stretches or the resistance of the article to the stretching force. A controller preferably compares the reaction of the article to a predetermined set of reactive values corresponding to the respective first and second portions of the article.
One advantageous embodiment of the method and apparatus is in a system having a transport structure for conveying a plurality of the articles in sequence, with each article being randomly oriented with its first or second portion in a relatively leading disposition and the other portion in a relatively trailing disposition. Each article within the transport structure is presented in sequence to a processing station at which the stretching force is applied to the leading or trailing end of each article. Preferably, a suitable arrangement is provided for controlling the subsequent handling of each article in response to the sensor or other device detecting the manner in which the article reacts to the stretching force. For example, each article with its first portion in a leading disposition may be handled in one manner for subsequent processing, while each article having its second portion in a leading disposition may be handled in a different manner for subsequent processing.
A particularly advantageous application of the present method and apparatus is in a system for handling textile goods, especially hosiery items having a toe end and a cuff end of differing stretch characteristics. The method and apparatus may be arranged such that each hosiery item having the toe end in a leading disposition is simply permitted to continue in the same orientation along the transport structure, but each hosiery item having its cuff end in a leading disposition is reversed before continuing conveyance within the transport structure.
These and other features, details and advantages of the present apparatus and method will be recognized and understood by those persons skilled in the relevant art from the following detailed disclosure of the invention with reference to the accompanying drawing.